DESCRIPTION( Taken by Applicant): Medicare's End-Stage Renal Disease (ESRD) program is the only public program that provides health insurance coverage for a specific disease. ESRD patients typically survive fewer than five years after beginning renal dialysis. During this time they average 1.9 hospitalizations per year, for a total of 14 days. Previous studies have reported significant variations in a dialysis facility management practices, treatment costs and profitability. However, little is known about the relationships between dialysis facility characteristics and long-term dialysis patients' clinical and economic outcomes. We hypothesize that dialysis facility characteristics primarily influence total medical costs by modifying dialysis patient hospital events (frequency and type). Additionally, we hypothesize that changes in dialysis facility management practices may improve long-term clinical outcomes for dialysis patients and for the ESRD system as a whole. However, these changes may also increase dialysis facility operational costs. Using information from three consecutive years of incident dialysis patients with a minimum of one and a maximum of three years follow up on all patients, this project will evaluate these hypotheses. Follow-up will begin on the 91 days after dialysis initiation and continue until death or renal transplantation. After adjusting for differences in patient clinical characteristics, we will define the impact of dialysis facility characteristics on dialysis patients: (1) mortality (survival and life expectancy), (2) morbidity (hospitalization rates and event-free survival, death, or hospitalization) and (3) total medical costs (dialysis treatment, hospitalization, physician and supplies). We will then assess the economic attractiveness (cost-effectiveness or cost-savings) of dialysis facility management practices that improve dialysis patient long-term clinical outcomes and develop decision models for the dissemination of study results. Through these aides, dialysis patients, providers, payers and policy maker will be able to: determine how dialysis facility management practices impact long-term clinical and economic outcomes and identify optimal management practices to improve survival or decrease total medical costs for dialysis patients.